Atherosclerosis begins in childhood. The extent and progression of atherosclerosis is related to low density lipoprotein (LDL) levels. LDL levels persist over time, but can be altered by diet. The overall aim is to investigate the efficacy, safety, feasibility and acceptability of dietary intervention in children with high LDL. A sample of children 8-10 years old with LDL cholesterol (C) greater than the 90th percentile will be selected from a representative sample of the children in the New Orleans Public and Catholic Schools. Initially, 20 children will enter a 16-month feasibility study. Later 80 children will enter a 3-4 year clinical trial. The children will be randomized to return to the usual medical care (UC) or to a special care (SC) diet intervention. The special care diet will be low in fat, saturated fat and cholesterol (Phase I of the American Heart Association). We will compare in UC and SC the changes in eating behavior, nutrient intake, nutritional status, lipids, lipoproteins, and examine the determinants of response to the diet and the impact on psychosocial function. The clinical trial will be conducted in collaboration with five other clinics and the NHLBI staff.